Photographic camera



Dec. 15, 1936. H, C; DECKEL 2,064,341

PHOTOGRAPHIG CAMERA Filed Oct. 28, 1935 Per? f L IN VEN TOR.-I'SATTOREEY jPatentedDec. 15, 1.936

7 UNITED v STATES A PATENT oFFics -auun nsrmc cams ,Hans C. Deckel,Scllninear Hnniciadcrmany, Signor to Friedrich Deckel, Munich-,PrinaLlulwllalmhe,V

.sppuuen october za. im, sei-m No. 46,084

In Germany December' 12, 1933 "achim (cias-44.

This invention relates to photographic cameras of the type including annder lens and a photographic lens, both of which are adjustable foraccurate focusing, and especially to such a camera in which. thephotographic lens may be removed and `replaced by another photographiclens oi dif- !erentiocal length.

An object of the invention is theprovision of a Y generally improved,simplined, and more factoryarrangement for focusing the two lconcomitantly.

Another object of the invention is the provision of focusing mechanismso designed that when one photographic lens is removed and is replacedby g l in certain improvements and combinations oi' parts, all as willbe hereinafter more fully described, lthe` novel features being pointedout in the claims at the end of the speciilcation.

In the drawing:

Fig. 1 is a schematic cross section through the front of a cameraembodying the present invention, and I Y Fig. 2 is a view of a differentphotographic lens, such as a telephoto lens, which may be used in placeof the photographic lens shown in Fig. 1.

The same reference numerals throughout the several views indicate thesame parts.

The camera is provided with 4a. front wall i in which is inserted afront plate 2 held to the wall I by any suitablemeans vsuch, as by thescrews shown in the drawing. This plate 2 carries suitable aperturesforreceiving a iinder lens 3 and a photographic -lens 4. Preferably-theaperture for receiving the ilnde'r lens is surrounded by an annularilange 5 internally threaded to cooperi ate with screw threads i on theholder of the ilnder lens. Thus when the nder lens is rotated, as bymeans of the knurled ilange i1 'accessible at the front of the camera,this rotationA what similar to the ange 5 but formed separate-V ly fromthe plate 2 instead of being integral with it'. This nange I extendsthrough a suitable'y opening ln the plate 2, as shown, and is heldsecurely in this opening byrany suitable fastening means. not shown indetail in the drawing,

with a ring or projection seated tlrmly against the 5 front face of theplate 2 so as to position the threaded ilange l accurately in a fixedlocation with respectlto the plate 2.

Mounted on therear side of the plate 2 is an annular gear l, cc-axialwith the lens 4 but of 10 larger diameter than the lens, and havingteeth Il cut around its circumference.` The gear 9 may be held by anysuitable fastening means, such as a ring la suitably held tothe back ofthe plate 2 and engaging an annular slot in the gear. l5

The gear teeth Il on this gear 9 are engaged with the teeth of the gearii secured to the rear end of the holder of the ilnder lens 3 so that asthe iinder lens ls rotated to move it axially for focusing, it willcause corresponding' rotation ci? the zo gear I. It willbe noted thatthe gear 9 is relatively wide, so that the gear -li will remain inproper engagement with the teeth lil of the gear l in all positions towhich the gear il may be axially displaced within the range of adjust-25 ment of the ilnder lens. A

A suitable detachable connection is provided between the' gear 9 and theholder of the photographic lens 4, for turning the lens when the gear' 9is turned. This connection may comprise, for 30 example, two or moreaxially extending grooves i2 in the inner peripheralface of the annulargear 9; with vwhich may be engaged a correspond# ing number of radiallyextending lugs I3 on the ilange i4 securedtothe rearendot the threaded35 graphic lens and will cause corresponding rota- 4o tion of that lensrelative to the stationary ilange I, thus moving the photographic lensin an axiai direction by virtue of the'screw threads 1. so that thislens is focused. During the axial focusing movements of the lens 4, thelugs i3 will slide 45 axially along the groovesv I2, but without beconr`IDU disengaged from them.

The pitch of the screw threads i is so related tothe pitchofthethreads'landtothei'ocal length of the respective lenses, that acertain rotation ci the ilnder lens which causes proper axialdisplacement to focus it for a certain distance, will alsocause just theright amount of axial displacement of the photographic lens to focusit-ior the same distance. With arrangement, the photographic lens mayeasily be replaced by another lens having a different focal v length, ifdesired, and no change will be required in the focusing mechanism otherthan the mere substitution of one lens holder for another lens holder,if only the pitch ofthe screw threads of each separate photographic lensholder .is designed in accordance with the focal length When theassemblage is in place in the camera, lugs'l on the flange 8 may extendinto the slots 'I'he photographic lens .and its holder and thecorresponding threaded ange l constitute an i5 in the plate 2 to holdthe ange I against rotation with respect to the plate 2. Ror example,

one of the different lens assemblages provided with the camera maycomprise a telephoto lens i8 (Fig. 2) having a holder provided, asbefore, with screwv threads 1 and with a flange Il having lugs I3 toengage the slots i! in the gear ring 9. The internally threaded flangeIl surrounding the threads 1 of the telephoto lens is similar to theflange 8 previously described, except that it may conveniently be madelonger in order to hold more securely the longer telephoto lens. Becauseof the greater range of focusing movement of the telephoto lens, anannular sleeve 1l.

secured to the lens holder, may extend rearward-l ly in. overlappingtelescoping relationship to the ilange I9, las plainly shown in thedrawing, so

as to protect thefront end portion of the threads V`l from damage ordirt when the lens is adjusted vto its most forwardposition with respectto the sleeve I9.

In such a telephoto lens, the pitch of the screw threads `would besomewhat different from the pitch of the threads used on a lensofdifferent focal length, as already explained, butthe' pitch of thethreads is chosen by the manufacture in accordance with his knowledge ofthe require- I ments'of'- each individual lens. and nothing is requiredof the user of the camera except the simple act of taking out one lensassemblage and slipping the other desired lens assemblage into place.the screw threads of differentpitch) are all in- :luded in each unitarylens assemblage, there Aare no separate parts to be lost or misplaced,or tobe accidentally put together in a wrong manner by the user of the'camera. No change in the gearing between the finder lens and thephotographic lens is required. Yet at all times, a focusing of one lenswill accurately focus theother 4in a simple manner and withtheutmostnicety.

While one embodiment of the invention has been disclosed, it .is tov beunderstood that the inventive idea may be carried out in a number ofways. This application is therefore notto be or the scope of theappended claims.

to the p recise details described; but isintended to cover allvariations and modifications' thereof falling within the spirit of theinvention rclaim: 1. 'A photographic. camera comprising er lens will beoperatively connected to eachother .relatively to said member it willmove longitudi- Inasmuch as the variable factors (i. e.,

'av detachable and replaceable photographic lens, a finder lens, meansfor focusing each of said lenses, said means including screw threads,and'interconnecting mechanism for operating the means for focusing oneof said lenses upon operation of the 5 means for focusing the other ofsaid lenses, at least a part of said interconnecting mechanism beingpermanently associated with and bodily detachable/and replaceable withsaid photographic lens.

2. A photographic camera comprising a photographic lens, a finder lens,meansfor focusing each of said lenses, one of said lenses and part ofsaid fccusin'gmeans constituting a unit bodily removable from andreplaceable in the camera, and interconnecting mechanism for operatingthe means for focusing one of said lenses upon operation of the meansfor focusing the other of said lenses.

3. A photographic camera comprising a finder lens, a plurality ofremovable and interchangeable photographic lenses, means for focusingeach of said lenses, said focusing means for said photographiclensesbeing at least in part associated with and removable bodily as aunit with each of said lenses, and interconnecting mechanism effectivewhen one of said 'photographic lenses is mounted in said camera foroperating the means for focusing one of said lenses upon operationof themeans for focusing the other of said lenses.

4. A photographiccamera comprising. a finder lens mounted for focusingmovementfinterconnecting operating mechanism movable in accordance withthe focusing movements of said nnder lens, and a plurality of removableand replaceable photographic lens'units, each unit including aphotographic lens of characteristics different from those of the lensesof the other units and further including, as an integral part of theunit, means adapted to the particular characteristics of said lens forcooperation with said-interconnecting operating mechanism duringfocusing of said photographiclens, so that when any one of saidphotographic lens units is placed in operative position in the camera,the photographic lens and the findfor concomitant corresponding focusingmovement without any change in said' interconnecting operatingmechanism.

5. A removable and replaceable photographic lens unit for cameras,comprising an internally` threaded hollow member for attachment to acamera, an externally threaded lens holder extending into andcooperating with the threads of said hollow member so that whenholder'is turned nally for focusing, a lens mounted in said holder, andlug means extending outwardly from said holder for vremovable engagementwith means for vturning said holder to focus said lens. l

. able connection between said gear and said Dhotographic lens vholderfor transmitting rotary' movements ofv one to the other, and gear meansoperatively connecting said annular gear to said Y finder lens holder so'that' rotation of one of said lens holders will produce rotation of theother of said lens holders for concomitant focusing of lenses held bysaid two'holders.

7'. A photographic camera comprising a screw 75 threaded ilnder lensholder rotatably mounted for lfocusing, a removable and replaceablescrew threaded photographic lens holder rotatably mounted for focusing,an annular gear permanently mounted in said camera in a position sur- Arounding said photographic lens holder, cooperating means internally ofsaid gear and externally of said photographic lens holder foroperatively connecting and disconnecting one from the other holders.

HANS C. DECKEL.

